Single-crystal lithium nickel cobalt manganate precursor and preparation method thereof and single-crystal lithium nickel cobalt manganate

Abstract

The invention provides a single crystal lithium nickel cobalt manganate precursor and a preparation method thereof. The preparation method comprises the following steps: preparing a mixed salt solution, a precipitant solution and a complexing agent solution, and introducing a mixed gas of oxygen and non-oxygen in a volume ratio of 1:19-1:29 into a reaction kettle at a flow rate of 7-20 L/min; adding the mixed salt solution, a sodium hydroxide solution and an ammonia water solution at a flow rate of 60-120 ml/min for reaction; and keeping the pH value at 10.0-11.0, a temperature at 30-60 DEG Cand a stirring rotating speed at 100-500 rpm to obtain the single crystal lithium nickel cobalt manganate precursor, wherein the thickness of the primary particle sheet layer is 100-200 nm, the particle size D50 is 3.0-4.0 [mu]m, and the particle size distribution (D90-D10)/D50 is less than or equal to 0.8. According to the invention, the secondary particle size D50 of the precursor prepared by the method is 3.0-4.0 [mu]m, and the particle size distribution is not more than 0.8; and the single crystal lithium nickel cobalt manganese oxide particles prepared by the precursor are narrow in particle size distribution and good in high and low temperature performance.

Description

technical field [0001] The invention belongs to the field of positive electrode materials for lithium ion batteries, and in particular relates to a precursor of single crystal nickel cobalt lithium manganese oxide, a preparation method thereof and single crystal nickel cobalt lithium manganese oxide. Background technique [0002] In the field of new energy electric vehicles, ternary material lithium-ion batteries are widely used in electric vehicles due to their good safety performance and low cost. However, the disadvantages of ternary materials for lithium-ion batteries, such as unstable high and low temperature cycle performance and low specific energy, still restrict the practical application of ternary materials. Conventional nickel-cobalt-manganese ternary materials have a spherical secondary particle structure formed by agglomerating dozens or hundreds of primary particles. This agglomerated material has a low compaction density, and the particles are easily deformed ...

AI Technical Summary

Problems solved by technology

However, because the inside of the secondary particles is too loose, the porosity is too high, the median particle size of the secondary particles is large, and the electrical performance and energy density of the precursor are low.

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